Shigellosis is an acute inflammation of the intestines caused by infection with a Shigellabacterium and is a major cause of dysentery (i.e. a severe form of diarrhea). The infection is highly contagious and usually short-lived but severe.

Shigella is a gram-negative bacterium that is part of the Entrobacteriaceae family. Four species can be distinguished, i.e. Shigella dysenteriae, Shigella flexneri, Shigella boydii and Shigella sonnei, which has several serogroups.

Shigella causes acute intestinal infections with symptoms such as fever, abdominal pain, diarrhea, tenesmus (false/painful sense of urgency) and sometimes vomiting. Diarrhea containing blood or mucus is sometimes also encountered after a few days, and additional symptoms like muscle pain, headache and skin rash can also be experienced. The infection is usually short-lived but severe, sometimes with bowel movements up to 20-30 times a day. The time between becoming infected and developing symptoms is usually 1 to 7 days.
Shigellosis can also be associated with complications such as dehydration, intestinal disorders and, in severe cases, blood poisoning (sepsis). 

Shigella dysenteriae produces the shiga toxin, which causes an infection that is much more severe, longer lasting and more likely to be fatal. This pathogen is responsible for epidemics, mainly in developing countries, with children under the age of 5 the main victims.

Humans and certain primates are the only reservoir of this bacterium and infection occurs through direct fecal-oral contact or through food, water or equipment (such as toilets) that has been contaminated by a sick person. This bacterium multiplies in the intestines of an infected person and ends up in the stool. In case of poor hygiene, the bacterium can be spread further via the hands. The bacterium can also be transmitted via sexual contact (sexually transmitted infection), mainly in men who have sex with men. 

Transmission of the Shigellabacterium can be prevented by taking hygiene measures. It is important to wash your hands carefully every time you go to the toilet, and before preparing or eating food. Also make sure that toilets are kept clean and be careful when changing diapers of children who may be infected with the bacterium.

In addition, avoid sexual contact with your partner(s) until the symptoms have disappeared for at least two weeks. 

Take extra hygiene measures when traveling to (sub)tropical countries with regard to food and drinking water, and wash your hands regularly. 

The doctor will take a sample of the patient’s stool and send it to a laboratory for a culture (coproculture). The diagnosis of shigellosis will be confirmed if the Shigella bacterium is isolated in the stool.

The laboratory will send the human bacterial strain to the National Reference Center for Shigella at the Bacterial Diseases department of Sciensano.

The risk groups for shigellosis are:

• people traveling to (sub)tropical countries
• relatives of people who are ill, mainly children
• men who have sex with men.

Shigellosis does not usually require any special treatment. Care should be taken to avoid dehydration by drinking plenty of water and consuming sufficient quantities of salt. The disease usually clears up on its own within a week. Antibiotic treatment can be used if the disease becomes serious or if there is too great a risk of contaminating others.